The mammoth B-15A iceberg appears poised to strike another floating Antarctic ice feature, a month on from a passing blow that broke off the end of the Drygalski ice tongue. As this Envisat image reveals, this time its target is the ice tongue of the Aviator Glacier.

Maps of Antarctica need to be amended. The long-awaited collision between the vast B-15A iceberg and the landfast Drygalski ice tongue has taken place. This Envisat radar image shows the ice tongue â€“ large and permanent enough to feature in Antarctic atlases - has come off worst.

The threat of sea access being blocked to US and New Zealand bases in Antarctica may have receded after the world's largest iceberg broke free from the McMurdo Sound sea bed last month, New Zealand Antarctic officials said.

Envisat radar imagery confirms that the B-15A iceberg â€“ the world's largest floating object â€“ is adrift once more after two months aground on a shallow seamount. This latest development poses a renewed threat to the nearby pier of land-attached ice known as the Drygalski ice tongue.

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